Gunsmithing Rough Chamber...Any Way To Fix?

[Brandon05_88]

The chamber on my factory Rem 700 .243 is rough in the shoulder area. I say this because I had it apart this weekend cleaning and prepping for bedding. Anyways, using a flashlight I noticed there were some machining marks still in the shoulder area of the chamber. I took a polymer cleaning pick and was able to feel very slight 'steps' on the shoulder. I looked at some fireformed brass and noticed they showed some very faint rings all the way around the shoulder from the machining marks. Again, this is the factory barrel from Rem. with only 268 rounds down it. Is it possible to have a gunsmith clean this up with a reamer, set the barrel back some and headspace and all that good stuff? Or would it be better to wait until the time to re-barrel?

 

[gunnergirl81]

Re: Rough Chamber...Any Way To Fix?

Other than marking the brass is it causing any other problems? That might fall under the old "if it ain't broke don't fix it" saying. Its a factory barrel, and if it shoots well, and extracts I wouldn't mess with it. Why spend the money fixing a cosmetic issue instead of saving the money for the next (better quality) barrel?

 

[monteboy84]

Re: Rough Chamber...Any Way To Fix?

I'd have a smith shove a .243AI reamer in there, that should handle it

-matt

ETA: I've seen a bunch of factory chambers that marked brass like what you're describing, I really don't think it will hurt accuracy any more than the factory chamber specs will.

 

[Brandon05_88]

Re: Rough Chamber...Any Way To Fix?

The rifle is shooting and extracting flawlessly, but I wasn't so sure about it being so rough. I like the velocities a .243AI can achieve, but I don't really want to replace the dies I already have then fire form again. I think I'll leave it as is until it's time for a new tube. Thanks for the responses!

 

[gamma]

Re: Rough Chamber...Any Way To Fix?

Leave it alone, theres nothing wrong with it.

 

[LRI]

Re: Rough Chamber...Any Way To Fix?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: monteboy84</div><div class="ubbcode-body">I'd have a smith shove a .243AI reamer in there, that should handle it

-matt

ETA: I've seen a bunch of factory chambers that marked brass like what you're describing, I really don't think it will hurt accuracy any more than the factory chamber specs will. </div></div>




Contrary to popular belief its not that simple. PO Ackley designed his cartridges to have a .004" crush at the neck/shoulder junction when fire forming. -meaning the parent case should "squish" a teeny bit when chambering. This is to ensure the case head is against the bolt face. This makes it so the parent case only grows/changes shape up front. To ignore this invites the web becoming elongated/stretched because the cartridge will move forward until the shoulders catch up with one another and stop movement. Now there's a gap between the boltface and case head. The cartridge fires and pressure being what it is, causes the case to grow from the middle out in both directions. (BAD!)

This <span style="font-style: italic">requires</span> taking a turn or two off the tennon and setting the barrel back. To ignore this will still make an ackley of sorts but it won't headspace and it won't provide the assurance that the case will grow only in the forward position.

Do an overlay of the prints once. There's no way to chase the parent case and make a true Ackley cartridge without setting the barrel back. On Remmy's its generally able to be done with a single rev. (.0625")

This is why Thompson Center break action single shots are near impossible to do. Can't really set the barrel back. Any screw on barrel however should make this relatively easy work.

Hope this helped.

C